Ultrathin dielectrics, oxides and oxynitrides were grown using microwave afterglow oxygen and N2O plasma at low temperature. N2O plasma annealing and pretreatment improved the breakdown properties of O2 plasma oxides. From secondary ion mass spectroscopy (SIMS) analysis, nitrogen was found to be incorporated into oxides effectively by this low-temperature method. Nitrogen content was highest at the oxide surface and decreased toward the oxide/Si interface. This indicates a nitridation mechanism different from the conventional N2O gas annealing or oxidation processes. The relationships among interface state densities, tunneling current and nitrogen profiles were also investigated by C-V and I-V measurements.

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Ultrathin (Ba,Sr)TiO3 (BST) film capacitors with a Pt/Ba0.5Sr0.5TiO3(30 nm)/Pt/TiN/Si structure were fabricated. To investigate the effects of annealing temperatures, capacitors were annealed in flowing Ar or O2 at temperatures ranging from 400°C to 600°C for 30 min. The electrical properties of the annealed samples were strongly dependent on the annealing temperatures. In the capacitors annealed at 500°C (in Ar and O2) and 550°C (in O2), the leakage current decreased to a level of 10-8 A/cm2 when the bias voltage was ±1.5 V. In the as-deposited sample, the maximum capacitance appeared at a bias voltage of -1 V. However, the maximum capacitance increased and appeared at the zero bias voltage after annealing. These phenomena are believed to be defect-related (due to oxygen vacancies). The annealing atmospheres were also found to have an effect on preserving the morphology of the Pt electrodes.

Microwave afterglow plasma oxidation at a low temperature (600 °C ) and rapid thermal annealing (RTA) were combined to grow high quality ultra-thin dielectrics. This new approach has a low thermal budget. The mid-gap interface state density of oxides pretreated in N 2 0 plasma was decreased to about 5 X 1010 cm-2 eV-1 after rapid thermal annealing at 950 °C. It was found that RTA is very effective for relieving the oxide stress and reducing the interface state density. Nitrogen incorporated in oxides by the N 2 0 plasma pretreatment of the Si surface helped to reduce the interface state density. Microstructures of ultra-thin oxide grown by microwave afterglow oxidation with or without RTA were revealed by extended-X-ray-absorption-finestructure (EXAFS) and X-ray photoelectron spectroscopy (XPS) analysis.

Titanium silicide was formed on the top of Si wafers by arsenic ion beam mixing and rapid thermal annealing. Three different arsenic-ion mixing conditions were examined in this work. The sheet resistance, residue As concentration post annealing and TiSi2 phase were characterized by using the* four-point probe, RBS and electron diffraction, respectively. TiSi2 of C54 phase was identified in the doubly implanted samples. The thickness of the Ti silicide and the TiSi2/Si interface were observed by the cross-sectional TEM.